/**
 *    Copyright (C) 2021-present MongoDB, Inc.
 *
 *    This program is free software: you can redistribute it and/or modify
 *    it under the terms of the Server Side Public License, version 1,
 *    as published by MongoDB, Inc.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    Server Side Public License for more details.
 *
 *    You should have received a copy of the Server Side Public License
 *    along with this program. If not, see
 *    <http://www.mongodb.com/licensing/server-side-public-license>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the Server Side Public License in all respects for
 *    all of the code used other than as permitted herein. If you modify file(s)
 *    with this exception, you may extend this exception to your version of the
 *    file(s), but you are not obligated to do so. If you do not wish to do so,
 *    delete this exception statement from your version. If you delete this
 *    exception statement from all source files in the program, then also delete
 *    it in the license file.
 */

#include "mongo/db/process_health/health_observer_registration.h"

#include <utility>

namespace mongo {
namespace process_health {

namespace {

using HealthObserverFactoryCallback =
    std::function<std::unique_ptr<HealthObserver>(ServiceContext* svcCtx)>;

// Returns static vector of all registrations.
// No synchronization is required as all the factories are registered during
// static initialization.
std::vector<HealthObserverFactoryCallback>* getObserverFactories() {
    static std::vector<HealthObserverFactoryCallback>* factories =
        new std::vector<HealthObserverFactoryCallback>();
    return factories;
}

}  // namespace

void HealthObserverRegistration::registerObserverFactory(
    std::function<std::unique_ptr<HealthObserver>(ServiceContext* svcCtx)> factoryCallback) {
    getObserverFactories()->push_back(std::move(factoryCallback));
}

std::vector<std::unique_ptr<HealthObserver>> HealthObserverRegistration::instantiateAllObservers(
    ServiceContext* svcCtx) {
    std::vector<std::unique_ptr<HealthObserver>> result;
    auto factories = *getObserverFactories();
    for (auto& cb : factories) {
        result.push_back(cb(svcCtx));
    }
    return result;
}

void HealthObserverRegistration::resetObserverFactoriesForTest() {
    getObserverFactories()->clear();
}

}  // namespace process_health
}  // namespace mongo
